Apparatus for forming clay pipe and the like



May 28, 1946. R. F, DONAHEY v APPARATUS FOR FORMING CLAY PIPE AND THE LIKE Filed June 4, 1943 2Sheets-Sheet 1 INVENTOR.

jp/vAazn ATmENEYs May 25,- 1946.

APPARA'IIUS FOR FORMING CLAY P IPE AND THE LIKE Filed June 4, 1943 2 Sheets-Sheet 2 INVENI'OR. 22035227" FIDO/VA HEY A m'EA/EV R. F. DONAHEY v 2,401,232

Patented May 28, 1946 APP RA US FOR FORMING CLAY PIPE AND THE LIKE 7. Robert F. Donahey, Shaker Heights, Ohio, assign- I i or to The Donahey Clay Products (30., Cleveland,

Ohio, a corporation ofDhio Application June 4, 1943,

p 1 Claim. (01. 25-39) My invention is an improvement in the art of eter of the section, that is, to form. an external producing ceramic articles and more particularly relative to anapparatus for forming hollow ceramic articles such as tile, septic tank sections and the like. I

Itv is one of the objects of the present invention to -produce hollow ceramic articles with an internal peripheral flange within the confines of the wallof said article. 1 -Another.object of the invention is the method of (producing articles of the above named character, which includes among other steps, the step or operation whereby the range is formed simultaneously with the'forming of the article i A further object of the invention consists in producinghollow ceramic articles of the above named character by a 'continuous method.

A further object of the invention consists in the provision of hydraulic means whereby a forming member may be retained in proper forming position with respect 'to the mold during the forming operations and released by saidhydraulic means upon completion or the forming operation to permit withdrawal of the article from themold. Other objects and advantages of the invention will-become more apparent as the following de- 'scription of ,two; forms of the same progresses,

reference being made to the accompanying drawings in which like reference characters are employed to? designate like parts throughout the same. i i

In the drawings: 1

Figure 1 is a vertical section through an apparatus embodying my invention whereby an internal peripheral flange or lip may be formed ona hollow ceramic articlewithin one end thereof.

Figure 2 is a vertical section through an paratussimilar to that in Figure 1 but shows a modified arrangement of the hydraulic means for retaining the forming member in contact with the article during the forming operation.

Figure 3' is aside elevation of an apparatus embodying my invention taken in a direction approximately 90 fromthatshown in Figure 1.

In the manufacture of hollow ceramic articles such as pipe or septic tank sections it is desirable to forms, lip or flange on one end of the section to receive the :unfianged end of an assembled adjacent section. It has been the practice to form a lip or flange at the lower end of the section as it is extended or pressed through a forming die but. so far as I am aware these flanges have always been formed outwardly of the diam- Serial No. 489,664

socket to receive the unflanged'endof an adjacent section so that the=walls of each section will be in alignment with each other. i i

i The present invention relates to means for forming a hollow article having a socketed-end in which the lip or flange is formed inwardly and downwardly of the section wall by causing a former to-be hydraulically engaged with the bell and the die of the press during the lip or flange forming operation.

The invention will be better understood from the following description of the embodiments shown in the accompanying drawings in which I have shown in Figure 1 apress of conventional member 4 is provided. with a duct or conduit 8 having connection through a pipe Swith a vacuum pump (not shown).. The duct 8 communicates through the hollow central portion of the member 6, and the opening l0 withthe interior of the bell 3 for purposes which will be explained hereinafter.

The material to be extruded or pressed intoshape between the die and the bell is forcefully fed downwardly through the cylinder 1 between the radial arms 5 and into thespace between the die 2 and hell 3. As the material passes downwardly in this space the adjacent walls of the die and bell converge to a point where the desired thickness of the 'wall of the article to be formed is determined; and maintained. This is indicated at l2 in Figure 1.

I, have provideda simple means for forming or casting theend of the article with an internal annular up or flange l2a which extends inwardly of the inner diameter of. the article at l3 and downwardly of the end thereof at l4.. This means comprises a former plate J5 which is provided with an annular upstanding rib l6 adapted to lie. against the inner lower wall ll of the die section lB. The, rib I6 is spaced from the outer lower wall 19 of the die, while the lower end of-the bell 31s relieved inwardly as at 20 to form the desired channellbetween the bell and the rib and the lower portion of the die section l8, for forming the said internal annular flange I211.

The former plate I 5 is also provided with an annular positioning and sealing abutment or rib 2! which is adapted to seat within the inner annular lower edge of the hell 3 as shown in Figure 1 when the former plate is in place. The abutting walls of the bell and the rib 2i arepreferably bevelled as shown', to insure a close fit and seal against passage of clay therebetween.

In this manner, when the former plate I5 is brought upwardly by raising the plunger or lift 22 upon which it is secured, the rib IE will enter the flange forming space between the lower bell and die walls. As the former plate approaches its uppermost position the positioning and sealing rib 2! will engage the inner lower bell wall and seal the former plate with respect to the bell. 4

Another important feature of the present invention resides in the provision of means for releasably retaining the former plate in contact with the lower end of the extended article during the internal lip forming operation. Such means may take the forms'hown inthe' accompanying drawings'and described briefly hereinbefore. Aconduit 9 having connection with a vacuum pump and a'suitable control valve (not shown) cornmunica'tes'with the interior of the bell 3 through the ducts 8 and HI. When the air between the former plate andthe interior of the bell is evacuated sufiiciently, the partial vacuum thus created within the bell will hold the plate in placeby virtue of the sealing eifect of the material [2a in contact with the plate l5 and the adjacent walls of the bell and die.

When the lip I20, has been formed, the operator may release the partial vacuum in the bell and remove the plate l5 by lowering the l ft 22 to the dotted line position shown in Figure 3.

It will be noted that the rails 23 on which the shod car 24 travels lie substantially tangent to the circular rib l6 when the former plate is lowered to the dotted line position in Figure 3. The wheels 25 of the car therefore maypass uninterruptedly from the rails to the rib [6 to sup'e port the shod car directly on the former plate.

A supporting-ring 2B of greenclay or other material and of the same diameter of'the rib li is placed'on the shod board on the car so that when the lift 22 is raised to the position in Figure 3 the ring 26 will enter the space formerly occupied by the rib IS in the formedend of the clay section l8. Thepurpose of the ring 26 is to take some of the load or weight of the section being formed where it is severed from the succeeding mass in the press, thereby preventing damage to'the relatively soft lip l2a, which would otherwise occur if the full weight of the section and/or the extruding pressure had to be supported on this offset member. The press-is now operated to extrude the cylinder section to the length where the same may be severed transversely. The pressure of extrusion. is sufiicient to cause the lift 22 to be loweredas the cylinder is being extruded.

When the cylinder or section. has been ex truded sufiiciently to expose the desired cylinder length below the lower edges of the bell and die, it may be severed from the following mass by means of a taut wire or blade 2'! movable below the said lower edges f the bell and die in a plane transverse to the axes thereof. The wire or blade is supported between rollers 28 which travel along the rails 29 as shown in Figure 1 and approximately at floor level and the carriage and the sections are rolled from the former plate onto the tracks 23 and transported to the dryer and then to the firing kiln.

This operation is repeated for each successive section formed and in this manner constitutes a continuous and systematic method to be carried out for the production of cylindrical sections of plastic material such as green clay, in which 7 each section is formed with an integral internal recess or lip within the outer diameter of the section, or, if desired, a succeeding section may be extruded in the manner just described after. the shod car has been rolled ofi the former plate and the carwith the previously formed section may be used as a support for the succeeding section. When sections are nested in this manner the'use of the ring 26 may be dispensed with after forming the first section.

By my method, I am enabled to produce hollow sections such as septic tank sections of green clay or other plastic material, having a recess or seat formed internally of the diameter of the section and at one end thereof. In sections heretofore made by various other methods the seat is formed externally of the section resulting in an outwardly projecting lip or flange.

This type of flange often becomes broken or mutilated before firing or even broken after firing and results in considerable loss both in material and production time. Furthermore these projecting flanges necessitate additional shipping and storage space. Such disadvantages are eliminated by my invention.

As pointed out above another important feature of the present invention is the use of hydraulic means to retain the former plate in sealed relation to the end of the section which is to be internally recessed.

In Figure2 I have illustrated a modified form of apparatus in which the air or other fluid within the bell 3 may be evacuated through a pipe 3| carried by the former plate, as distinguished from the form shown in Figure 1, where hydraulic communication is efiected through the head of the bell. The form of the invention shown in Figure 2 has the advantage of a more simplified construction.

Various changes may be made in the details of construction of the invention without departing from the spirit or scope of the appended claim. I

I claim:

An apparatus for forming vitreous clay products such as septic tank section, conduits or the like, comprising a die, a bell mounted within the die and coaxial therewith, means for extruding a mass of clay material downwardly between the die and the bell, the outer circumference of the bell adjacent the lower end of the die being reduced to provide a space between the die and the bell at the respective lower ends thereof of greater width than the forming space between the die and the bell, a former plate, removable means for moving said former plate into contact with the lower edges of the die and bell, said former having a sealing lip extending into the enlarged space between the die andthe bell and in contact with the inner wall of the die, said up in contact with the extruded and formedend of the section while the section is being extruded between the die and bell, shearing means operating transversely'across the lower ends of the die and bell for shearing the formed section when the same has been extruded through the die to the selected length.

ROBERT F. DONAHEY. 

